Using the identities, simplify :
(x2-9)
Using identity a2-b2=(a-b)(a+b)
(x2-9)=(x-3)(x+3)
Hence the result is (x-3)(x+3)
Using the identity, simplify the following:
(i) (a + 6)2, (ii) (3x + 2y)2; (iii) (2p + 3q)2; (iv) (x2 + 5)2.